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Crayfish, Crawdads, Yabbies, Ditch Bugs Parasitic Disease

FAQs on Crayfish Disease: Crayfish Disease 1, Crayfish Health 2, Crayfish Health 3, Crayfish Health 4, Crayfish Health 5, Crayfish Health ,
FAQs on Crayfish Disease by Category: Diagnosis, Environmental, Nutritional, Trauma, Infectious, Social,

Related Articles: Forget Crawfish Pie, Let's Make a Crawfish Tank! By Gage Harford, Invertebrates for Freshwater Aquariums by Neale Monks, Freshwater Shrimp, Crayfish, "Lobsters", Prawns Freshwater to Brackish Crabs

Related FAQs: Crayfish 1, Crayfish 2, Crayfish ID, Crayfish Behavior, Crayfish Compatibility, Crayfish Selection, Crayfish Systems, Crayfish Feeding, Crayfish Reproduction, Freshwater Invertebrates/Use in Aquariums, Freshwater Crustaceans for the Aquarium, FW Crustaceans 2, Fresh to Brackish Water Crabs, Hermit Crabs,

Epistylis on crawfish       9/14/18
Hi, my name is Susan, i have 6 Louisiana swamp crawfish that i rescued from one of our crawfish boils. In the last month they have developed a white fuzz all over them. the best i can tell from all the internet searching is that it is Epistylis. But i cant find anything on treating it. 3 of the crawfish are berried and some of the eggs on 1 also has the fuzz. Please advise on how to get rid of it. My perimeters are all good, and i do monthly water changes.
<Epistylis spp. are commensals, not parasites, so while they might be unattractive to look at, they don't do any actual harm. However, because they grow in water with plenty of planktonic algae and bacteria that they can feed on, they're seen as indicators of poor environmental conditions.
More specifically, high levels of organic material and mineral nutrients in the water. So your best approach to tackling them is two-fold. First, find out how to improve ambient conditions. More water changes/removal of uneaten food, more filtration, and less (wasted) food would all be part of this. Secondly, understand that since these ciliate Protozoans are attached to the exoskeleton of the crayfish, they will be "shed" during successful molting, in which case quick disposal of the old exoskeleton would be helpful. I would remind you of the need for iodine in the diet to ensure successful molting (for some reason moults frequently fail under aquarium conditions otherwise) and also for a source of calcium, such as unshelled shrimp, if you're going to remove the old moult (crayfish normally consume the moult, in part, to recycle the minerals). You could also try medications used against other ciliates (such as Velvet and Whitespot) but they are likely to be toxic to crayfish unless clearly stated as "safe for
invertebrates" on the packaging. Cheers, Neale.>

Crayfish translucent growths        10/7/17
Good day!
I impulse bought a 3" Tangerine crayfish and now I'm scrambling to buy the materials to cycle a 10g long tank but for now I'm keeping her in a small 2.5 gallon tub with a sponge filter until then. She recently molted (But lost some limbs because she had horrible shell rot from the shop) and now its been 13 days i have noticed growths from the stumps of her lost appendages!
<Indeed. These are likely 'benign' Protozoans, bacteria or fungi that grow wherever there's plenty of dead organic material. They're benign in the sense that they're not aggressive pathogens that will make your crayfish sick, but they're still undesirable. An antibacterial and antifungal medication known to be shrimp-safe (such as eSHa 2000) could be used here, alongside optimising environmental conditions. To a great degree this sort of 'fluff' grows on crayfish in tanks that have less than perfect cleanliness. The more gunk for them to feed on, the more the Protozoans and fungus will spread onto your crayfish.>
i don't have a test kit yet so i cant tell the parameters but i do a lot of partial water changes every other day and feed her veggies and sinking pellets.
She's acting so differently now and she's just scared of everything unlike before (maybe its because she also lost her claws).. but i digress, the growths look feathery and have spots in them, attached here is a photo i took of her in an ice cream container while i was cleaning the sand in her tub (there was rotting broccoli pieces hidden so it was stinking to high heaven)
<The photo isn't sharp enough to see exactly what the problem here, but for now, I'd assume the benign fluff described above rather than an aggressive crayfish parasite. Still, if you can get tack-sharp photos, sites like
PetShrimp.com have active forums with numerous experienced crustacean-keepers.>
Thank you for helping, I've added some antifungal meds (no copper) but i just want to help her get better soon.
<Understood. Good luck, Neale.>

Re: Crayfish translucent growths      10/8/2017
Thank you for the reply!!
Just adding again but here's another pic of Megatron i took the same day, is this photo better?
<Not really. It's not so much the size of the photo as the fact the bit of interest, the fluff around the legs, is basically a blurry mess with black speckles.>
its got dark spots and it worries me to no end.
<They look like baby crayfish, what with the black spots and all! Cheers, Neale.>

Cray fish worms, just using/reading WWM 5/12/09
I have had many crayfish over the years. Gimpyshrimp<his name was missing 3 legs and a pincher>
<Mmm... Crays should regenerate these in subsequent molts... see WWM re their health>
has the worms/parasites that come out by his eves, top of head, thorax, and every overlay of his shell.
<This is also covered>
This is the only crayfish that I have noticed them. I got 2 really good pictures of the worms on him. They need to be magnified 4x on my 4 meg camera. If you would like to see them write me back at XXXX my girlfriend will have to show me how. I am not good on the comp., just learning. I never saw one molt until I watched it on your site thanks very much
<Please read here: http://wetwebmedia.com/FWSubWebIndex/crayfishdisfaq.htm
and the linked files above. Bob Fenner>

Crayfish parasites? Hello Crew, I have had my first crayfish, Claudine (Claude till I realized 'he' was a 'she'!) for four weeks now. She's a Cherax quadricarinatus. She shed her skin five days ago, and since then I have noticed some sort of parasite on her. I have scoured your website, but not found anything quite the same in the links. They are opaque to white in colour (and seem to get whiter as they get bigger) and look like tiny slugs. I don't think they move that much, but certainly stretch out. They have little antennae of some sort, which wave in the water. I have spotted about five of them. The most obvious sits on her head (as in the first photo), she has another couple at least in the 'cavity' around the eye area, one nearer to her 'mouth' (second photo, you can see its head near the dark patch in the middle of the picture) which is very active when she feeds, and one in the joint of one arm. I don't think they bother her, apart from the fact that she seems to 'blink' (flicks her eyes inwards!) quite a bit more than she used to. They really bother me though! I don't know whether this is normal for crustaceans as I have never kept anything like this before. The measurements for nitrites, nitrites etc. are all normal, and following the advice on your website, I have added a drop of iodide. Do you know what they are, and whether I should/can get rid of them? Are they harmful? I haven't attempted picking her up before as she's quite new and I don't want to frighten her. I think the only one I may be able to remove is the one on her head, but would need any advice on how to pick her up! Many thanks indeed for your help, Kathryn <Kathryn, it's difficult to say precisely what these little animals might be. They could be parasitic, but it's more likely they are merely commensal, that is, they live on the crayfish but don't cause any direct harm. There are a few similar reports on the Crayfish FAQ page, here: http://www.wetwebmedia.com/FWSubWebindex/crayfishfaqs.htm  In any case, treatment is likely impossible. Anything toxic to the "worms" would be poisonous to the crayfish. You could of course pull them off with tweezers or forceps, but at a risk of harming the crayfish. You could remove the next molt as soon as you see it, on the theory that might lessen the chances of re-infection (though crayfish do best when allowed to eat their molts and recycle the minerals therein). Bottom line, best left alone. Cheers, Neale.>

Freshwater Crayfish Infested with White worms. (Branchiobdellida?) - 0713/2006 Hi to whomever reads my email. <Sabrina with you, today.> My little Procambarus clarkii (Leonid) has been living by himself for a while and has been doing ok, we bought a better sponge filter for him, and took him out to examine him as a checkup. We noticed the parasites <Your guess that these are Branchiobdellida is probably spot-on. Typically, these are harmless, but there may be some species that can damage the animal somewhat.> and have a Malachite green and Chitosan formula (Mardel Maracide) which we tried using on a fish (Betta). We counted at least 10 of them that were visible. Is this Maracide safe to use on a crayfish? <No. This is toxic (at best) to the Cray, and may even kill it. In general, it is best to just never use medications with invertebrates present. Most anything designed to kill parasites will harm pet invertebrates. If you feel you must remove these worms, do so manually by gently (gently!) scraping them off with a fingernail, cloth, or brush with the Cray submerged in a bowl of tank water.> Also, is there any possible way to prevent this from recurring? <Not effectively. Just remove as you see necessary.> One other question not related to the Worms, my other 2 crayfish are robustus, <Neat!> and one is female, the other male. If I choose to breed them, how much of a size difference between them can there be? <Preferably not significant, or the larger animal may damage the smaller one.> The male (Vladimir) is about an inch longer than the female (Mavra). <Mm, not quite descriptive enough.... I mean, if the male is 2" and the female is 1", this is a significant difference.... though, at that size, they're not going to breed :grin: If, on the other hand, the male's 7" and the female's 6", this is a fine size, and no worries.> All help appreciated, Colin. <All the best to you and your crayfish! -Sabrina>
Freshwater Crayfish Infested with White worms. (Branchiobdellida?) - II - 071*/2006
A more descriptive way to explain would be that measuring from tip of the head to tail, Vladimir is about 4 1/2 inches and Mavra is about 3 inches. I am thinking of waiting a while for Mavra to molt and I think this will allow her to get within a 3/4 of an inch of Vladimir, hoping she could possibly become 3 1/2 to 4 inches. <Sounds good. I might give it a little longer. Definitely wait until her shell's hardened completely - a few to several days after moulting, if possible.> They share a tank with a divider in the middle, and I see them looking at each other. Do you think this could be considered flirting? <Either it's crayfish love, or they're looking at each other as a potential dinner. I'd bet they're starting to feel amorous.> Also with the Cray and the meds, we had tried the meds before I received your most informative response, <Yikes!> he sat in the formula for a couple of hours and when I saw the email I quickly picked him out and changed the water. <Ahh, whew! I'm VERY glad to hear/read this. Thank you for acting quickly. All the best to you, -Sabrina>

Re: Freshwater Crayfish Infested with White worms. (Branchiobdellida?) Crayfish Continued - 07/27/2006
Dear Sabrina, <Hi, Colin!> I am very happy that I can email you using my Gmail's reply, you are the most valuable source of information about my freshwater crayfish. <Glad to be of service.> My dwarf frogs have died off, <.... why?> but left a nice open area for someone to live, I am considering getting a new 10 gal tank and giving it to Mavra, then Vladimir, being the bigger Cray, shall get the whole 15 gallons to himself. Would it be a good idea to introduce Vladimir to Mavra when we decide to, inside of the 10 gal, then allow Mavra to go through her short period of motherhood before moving her to somewhere else? <Possibly. Just be sure that there are LOTS of good nooks and crannies for her to hide in. A pile of PVC joints and elbows or clusters of rocks/caves would be good.> My father thinks some kind of Cleaner shrimp would help the tanks, but I am afraid the crayfish would just eat them, <Likely - but possibly they'd be ignored. I'd make an attempt with very inexpensive shrimp (like ghost/grass shrimp) if you try this.> if shrimp would not work, what else would be safe from the power of the Cray? <Maaaaaaybe snails.... Perhaps Septaria sp. snails would work best....> Big news with Mavra, her rear left leg is growing back. <Excellent!!> We noticed a small white pinkie growing out of her leg, and now it is growing larger. <This is a very clear sign of good health.> I appreciate all of your help and wisdom, Colin <As always, I'm glad to help out. Wishing you well, -Sabrina>

- Crayfish Parasites - I have two freshwater crayfish (they are probably Florida Crayfish and they are approximately 3" long) in an Eclipse Six Tank. We have had them a few months. I just noticed many parasites on them. They look like small white worms approximately 1/16 - 1/8" long. <Quite likely one or more varieties of Branchiobdella which is an obligate crayfish parasite.> I also see white specs all over the glass. How do I kill these parasites without killing the crayfish? <Hmm... well, I had to look this up on the Internet and actually used Google and put in the subject of your email, "Crayfish Parasite" - if this is indeed Branchiobdella then there is no known treatment. Do not introduce these crayfish into the wild or to other captive crayfish as the parasite will spread.> Please advise A.S.A.P. Thank you. <Cheers, J -- >

Crayfish parasites I have an electric blue crayfish which I purchased a couple of weeks ago at our local pet store. Over the past couple of days I have noticed some (5) small white creatures (approximately 1/8th inch) that are inhabiting around the nose and the base of the feelers. They look like a tube with 2 tiny arms at the top (one on each side) and as I was watching them one of them kind of flipped end over end to move up the crayfish's head. Also when I was feeding my other fish in the tank (33 Gal) and the flake food moved past one of these so called parasites it looked like it tried to grab it. Any ideas as to what these are or do you require further information. <I'm sorry I really am uneducated in crayfish other than catching them in the local creeks here, so I had to look up and see what I could find. You might look at this site which seems to really have a handle on crayfish http://us.geocities.com/crayfishdisease/pages/intro.html. Good luck, MacL> Thanks, James

Crayfish With Ich? - 12/13/2004 Hi, I was wondering if crayfish can get ich. <No. Ich (Ichthyophthirius multifilius) is an obligate fish parasite - the Cray cannot be affected by ich. A Cray can, however, have ich cysts stuck to it, while the cysts are reproducing and before they become free-swimming in search of fish. These would be totally invisible to the naked eye, and can be stuck to anything from an infected tank - gravel, plant, and crayfish alike.> I have one that I saved from the feeder goldfish tank at my work. Once I got it home I realized it has what looks like ich on it. <It's more likely either his coloring or bits of detritus stuck to him. I wouldn't be terribly worried.> I can't seem to find any info on treating crayfish with ich though, which made me wonder if it is ich at all. <Very, very highly unlikely.> I do not want to introduce him to my tank if he could make all my fish sick. <As above, he can have (invisible) cysts stuck to him - I wouldn't be too worried, but it would be best to quarantine him anyway, as it is best to do before introducing any animal to your established tank.> I have a 20 gallon heavily planted (swords, and frills) tank with one Creamsicle and one silver Lyre-tail (sp?) molly, their new fry, a dragon fish, <This common name is applied to a few different critters.... but any one of them (Polypterus sp., Erpetoichthys sp., Gobioides sp.) will all outgrow a 20g tank in short order - and the last, Gobioides, is a brackish animal. Please research this fellah a bit, find out what you have, and what your options for it might be.> a rummy nose tetra, and a gold mystery snail. I really don't want to get ich and have to uproot my whole tank. <Agreed. Ich sucks.> Any info would be great. <As above, your absolute safest bet is to quarantine *any* new livestock before adding to your tank. BUT - this is pretty important - a crayfish really isn't a good tankmate for any of the fish that you've mentioned; any/all of them are more than likely to end up as crayfish food eventually. I urge you to set up a new tank for the Cray (even just a very, very simple 10-gallon setup would suffice). One cool bonus is that this is more than likely Procambarus clarkii, and you would not at all need a heater for his tank. Crayfish are unbelievably interesting animals to watch and care for, I think you would really appreciate him if you can give him a place to call home. I also urge you to read crewmember Gage Hartford's excellent and fun article in our online Conscientious Aquarist e-zine, on care and breeding of crayfish: http://www.wetwebmedia.com/ca/cav1i4/crayfish/crayfish.htm > Thanks, Candice <Wishing you and your crayfish well, -Sabrina>

Electric blue crayfish worms??? I have trying the product Maracide now for the past seven days and the worms are still on my electric blue lobster (crayfish). <Yes... this product is for infectious disease agents...> I have tried to take some pictures to show you <Very nice> but as I said before the worms are so small you can't really see them. He has a small white marking on the top of his head and near the bottom of his tail were the worms stick out of. He also has about a hundred or so on the bottom of his belly. The worms are not on anything else in the tank. I also have a blue crayfish in with him and about 25 or so guppies. None of which are infected. I am sending a few pictures and hopefully you will be able to see what I'm talking about. The worms in the picture are located in the middle of his eyes. Hoping to hear from you soon Thanks <Mmm, you can/could try actual Anthelminthics, compounds that are toxic to worms, but not (much) to other invertebrates. Please see here: http://www.wetwebmedia.com/fshwrmdisfaqs.htm and the next Related FAQ file, and the links where they lead you. Bob Fenner>

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